For relaxation to occur,
A. calcium leaves the sarcoplasmic reticulum, and troponin binds calcium and blocks the binding sites on actin.
B. calcium enters the myofibril, it detaches from myosin, and the binding sites on myosin become inactive.
C. sarcoplasm calcium levels fall, calcium is removed from troponin, and tropomyosin blocks binding sites on actin.
D. extracellular calcium levels fall, calcium is pumped into the myofibril, and tropomyosin slides away from actin.
C
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The mentalis muscle inserts on the
A) orbicularis oris. B) skin of the chin. C) angle of the mouth. D) hyoid bone. E) skin around the eyelids.
The connecting tissue of the two hemispheres of the cerebrum is the ____________________.
Fill in the blank(s) with the appropriate word(s).
Which structure functions in equilibrium?
A. Vestibule B. Cochlea C. Auditory ossicles D. Tympanic membrane
The viscous component of connective tissue matrix is called
A) basal layer. B) ground substance. C) collagen. D) lymph. E) plasma.